Cyclodextrin glucanotransferase (CGTase; EC 2.4.1.19) mainly produces cyclodextrins (CDs) using linear maltooligosaccharides. We performed site-directed saturation mutagenesis on the +1 substrate-binding residue, H233, of CGTase from alkalophilic Bacillus sp. I-5 to prepare specific-length oligosaccharides. The obtained mutant CGTase, H233Y, primarily produced maltoheptaose (G7) using β-CD via a hydrolysis reaction. A kinetic study of H233Y showed that the kcat/Km value of β-CD was 7-fold greater than that of G7, which accounts for the accumulation of G7 during the H233Y enzyme reaction. A structure comparison of CGTases with H233Y modeling suggests that the substitution of H233Y may alter the position of the +1 subsite and slow the further hydrolysis of G7 after the ring-opening reaction.
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http://dx.doi.org/10.1093/protein/gzv044 | DOI Listing |
Enzyme Microb Technol
January 2025
Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610213, China. Electronic address:
Natural products and their derivatives are precious resources with extensive applications in various industrial fields. Enzymatic glycosylation is an efficient approach for chemical structure diversification and biological activity alternation of natural products. Herein, we reported a stereoselective glycosylation of complex natural product glycosides catalyzed by two carbohydrate-active enzymes (CAZys).
View Article and Find Full Text PDFCarbohydr Polym
February 2025
Research Faculty of Agriculture, Hokkaido University, Sapporo 060-8589, Japan. Electronic address:
The glucoconjugation between linear chimeric α-(1→4)- and α-(1→6)-glucosidic segments exhibits functional properties throughout their structure. In this study, we enzymatically synthesized three new series of chimeric nonreducing isomaltomegalosaccharides (N-IMS-n/m), each featuring a constant n, α-(1→4)-segment (average degree of polymerization, DP = 22-25) at the nonreducing terminal, and varying m, α-(1→6)-main chain lengths (DP = 7-53). The synthesized compounds-N-IMS-25/7, N-IMS-24/19, and N-IMS-22/53-were compared to amylose (DP = 28) and previous samples of N-IMS-15/35 and D-IMS-28.
View Article and Find Full Text PDFFront Microbiol
November 2024
State Key Laboratory of Biobased Material and Green Papermaking (LBMP), Qilu University of Technology (Shandong Academy of Sciences), Jinan, Shandong, China.
Sci Rep
December 2024
National Engineering Research Center for Biotechnology, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.
β-cyclodextrin (β-CD) is an important cyclic oligosaccharide, which is widely applicated in foods, environmental protection, and cosmetics, primarily prepared from enzymatic synthesis in traditional industry. However, several challenges persist, including cumbersome processes and difficulties in achieving continuous fermentation and catalysis. This research introduced a biofilm-based immobilized fermentation, integrating with enzyme catalysis system of surface display in Bacillus subtilis.
View Article and Find Full Text PDFInt J Biol Macromol
November 2024
State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, Wuxi, Jiangsu 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, Jiangsu 214122, China. Electronic address:
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